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# Copyright (C) 2005, 2006 Canonical Ltd
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# Johan Rydberg <jrydberg@gnu.org>
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# This program is free software; you can redistribute it and/or modify
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# it under the terms of the GNU General Public License as published by
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# the Free Software Foundation; either version 2 of the License, or
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# (at your option) any later version.
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# This program is distributed in the hope that it will be useful,
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# but WITHOUT ANY WARRANTY; without even the implied warranty of
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# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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# GNU General Public License for more details.
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# You should have received a copy of the GNU General Public License
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# along with this program; if not, write to the Free Software
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# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
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"""Versioned text file storage api."""
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from bzrlib.lazy_import import lazy_import
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lazy_import(globals(), """
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from bzrlib.graph import Graph
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from bzrlib.transport.memory import MemoryTransport
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from cStringIO import StringIO
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from bzrlib.inter import InterObject
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from bzrlib.symbol_versioning import *
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from bzrlib.textmerge import TextMerge
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class VersionedFile(object):
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"""Versioned text file storage.
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A versioned file manages versions of line-based text files,
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keeping track of the originating version for each line.
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To clients the "lines" of the file are represented as a list of
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strings. These strings will typically have terminal newline
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characters, but this is not required. In particular files commonly
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do not have a newline at the end of the file.
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Texts are identified by a version-id string.
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def check_not_reserved_id(version_id):
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revision.check_not_reserved_id(version_id)
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def copy_to(self, name, transport):
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"""Copy this versioned file to name on transport."""
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raise NotImplementedError(self.copy_to)
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"""Return a unsorted list of versions."""
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raise NotImplementedError(self.versions)
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@deprecated_method(one_four)
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def has_ghost(self, version_id):
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"""Returns whether version is present as a ghost."""
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raise NotImplementedError(self.has_ghost)
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def has_version(self, version_id):
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"""Returns whether version is present."""
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raise NotImplementedError(self.has_version)
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def add_lines(self, version_id, parents, lines, parent_texts=None,
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left_matching_blocks=None, nostore_sha=None, random_id=False,
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"""Add a single text on top of the versioned file.
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Must raise RevisionAlreadyPresent if the new version is
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already present in file history.
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Must raise RevisionNotPresent if any of the given parents are
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not present in file history.
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:param lines: A list of lines. Each line must be a bytestring. And all
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of them except the last must be terminated with \n and contain no
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other \n's. The last line may either contain no \n's or a single
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terminated \n. If the lines list does meet this constraint the add
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routine may error or may succeed - but you will be unable to read
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the data back accurately. (Checking the lines have been split
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correctly is expensive and extremely unlikely to catch bugs so it
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is not done at runtime unless check_content is True.)
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:param parent_texts: An optional dictionary containing the opaque
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representations of some or all of the parents of version_id to
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allow delta optimisations. VERY IMPORTANT: the texts must be those
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returned by add_lines or data corruption can be caused.
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:param left_matching_blocks: a hint about which areas are common
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between the text and its left-hand-parent. The format is
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the SequenceMatcher.get_matching_blocks format.
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:param nostore_sha: Raise ExistingContent and do not add the lines to
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the versioned file if the digest of the lines matches this.
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:param random_id: If True a random id has been selected rather than
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an id determined by some deterministic process such as a converter
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from a foreign VCS. When True the backend may choose not to check
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for uniqueness of the resulting key within the versioned file, so
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this should only be done when the result is expected to be unique
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:param check_content: If True, the lines supplied are verified to be
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bytestrings that are correctly formed lines.
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:return: The text sha1, the number of bytes in the text, and an opaque
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representation of the inserted version which can be provided
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back to future add_lines calls in the parent_texts dictionary.
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self._check_write_ok()
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return self._add_lines(version_id, parents, lines, parent_texts,
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left_matching_blocks, nostore_sha, random_id, check_content)
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def _add_lines(self, version_id, parents, lines, parent_texts,
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left_matching_blocks, nostore_sha, random_id, check_content):
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"""Helper to do the class specific add_lines."""
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raise NotImplementedError(self.add_lines)
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def add_lines_with_ghosts(self, version_id, parents, lines,
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parent_texts=None, nostore_sha=None, random_id=False,
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check_content=True, left_matching_blocks=None):
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"""Add lines to the versioned file, allowing ghosts to be present.
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This takes the same parameters as add_lines and returns the same.
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self._check_write_ok()
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return self._add_lines_with_ghosts(version_id, parents, lines,
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parent_texts, nostore_sha, random_id, check_content, left_matching_blocks)
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def _add_lines_with_ghosts(self, version_id, parents, lines, parent_texts,
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nostore_sha, random_id, check_content, left_matching_blocks):
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"""Helper to do class specific add_lines_with_ghosts."""
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raise NotImplementedError(self.add_lines_with_ghosts)
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def check(self, progress_bar=None):
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"""Check the versioned file for integrity."""
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raise NotImplementedError(self.check)
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def _check_lines_not_unicode(self, lines):
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"""Check that lines being added to a versioned file are not unicode."""
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if line.__class__ is not str:
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raise errors.BzrBadParameterUnicode("lines")
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def _check_lines_are_lines(self, lines):
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"""Check that the lines really are full lines without inline EOL."""
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if '\n' in line[:-1]:
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raise errors.BzrBadParameterContainsNewline("lines")
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@deprecated_method(one_four)
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def enable_cache(self):
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"""Tell this versioned file that it should cache any data it reads.
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This is advisory, implementations do not have to support caching.
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@deprecated_method(one_four)
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def clear_cache(self):
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"""Remove any data cached in the versioned file object.
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This only needs to be supported if caches are supported
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@deprecated_method(one_four)
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def clone_text(self, new_version_id, old_version_id, parents):
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"""Add an identical text to old_version_id as new_version_id.
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Must raise RevisionNotPresent if the old version or any of the
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parents are not present in file history.
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Must raise RevisionAlreadyPresent if the new version is
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already present in file history."""
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self._check_write_ok()
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return self.add_lines(new_version_id, parents,
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self.get_lines(old_version_id))
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def get_format_signature(self):
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"""Get a text description of the data encoding in this file.
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raise NotImplementedError(self.get_format_signature)
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def make_mpdiffs(self, version_ids):
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"""Create multiparent diffs for specified versions."""
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knit_versions = set()
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knit_versions.update(version_ids)
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parent_map = self.get_parent_map(version_ids)
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for version_id in version_ids:
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knit_versions.update(parent_map[version_id])
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raise RevisionNotPresent(version_id, self)
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# We need to filter out ghosts, because we can't diff against them.
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knit_versions = set(self.get_parent_map(knit_versions).keys())
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lines = dict(zip(knit_versions,
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self._get_lf_split_line_list(knit_versions)))
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for version_id in version_ids:
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target = lines[version_id]
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parents = [lines[p] for p in parent_map[version_id] if p in
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raise RevisionNotPresent(version_id, self)
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left_parent_blocks = self._extract_blocks(version_id,
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left_parent_blocks = None
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diffs.append(multiparent.MultiParent.from_lines(target, parents,
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def _extract_blocks(self, version_id, source, target):
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def add_mpdiffs(self, records):
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"""Add mpdiffs to this VersionedFile.
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Records should be iterables of version, parents, expected_sha1,
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mpdiff. mpdiff should be a MultiParent instance.
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# Does this need to call self._check_write_ok()? (IanC 20070919)
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mpvf = multiparent.MultiMemoryVersionedFile()
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for version, parent_ids, expected_sha1, mpdiff in records:
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versions.append(version)
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mpvf.add_diff(mpdiff, version, parent_ids)
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needed_parents = set()
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for version, parent_ids, expected_sha1, mpdiff in records:
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needed_parents.update(p for p in parent_ids
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if not mpvf.has_version(p))
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present_parents = set(self.get_parent_map(needed_parents).keys())
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for parent_id, lines in zip(present_parents,
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self._get_lf_split_line_list(present_parents)):
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mpvf.add_version(lines, parent_id, [])
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for (version, parent_ids, expected_sha1, mpdiff), lines in\
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zip(records, mpvf.get_line_list(versions)):
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if len(parent_ids) == 1:
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left_matching_blocks = list(mpdiff.get_matching_blocks(0,
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mpvf.get_diff(parent_ids[0]).num_lines()))
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left_matching_blocks = None
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_, _, version_text = self.add_lines_with_ghosts(version,
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parent_ids, lines, vf_parents,
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left_matching_blocks=left_matching_blocks)
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except NotImplementedError:
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# The vf can't handle ghosts, so add lines normally, which will
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# (reasonably) fail if there are ghosts in the data.
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_, _, version_text = self.add_lines(version,
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parent_ids, lines, vf_parents,
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left_matching_blocks=left_matching_blocks)
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vf_parents[version] = version_text
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for (version, parent_ids, expected_sha1, mpdiff), sha1 in\
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zip(records, self.get_sha1s(versions)):
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if expected_sha1 != sha1:
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raise errors.VersionedFileInvalidChecksum(version)
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@deprecated_method(one_four)
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def get_sha1(self, version_id):
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"""Get the stored sha1 sum for the given revision.
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:param version_id: The name of the version to lookup
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return self.get_sha1s([version_id])[0]
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def get_sha1s(self, version_ids):
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"""Get the stored sha1 sums for the given revisions.
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:param version_ids: The names of the versions to lookup
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:return: a list of sha1s in order according to the version_ids
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raise NotImplementedError(self.get_sha1s)
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def get_text(self, version_id):
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"""Return version contents as a text string.
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Raises RevisionNotPresent if version is not present in
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return ''.join(self.get_lines(version_id))
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get_string = get_text
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def get_texts(self, version_ids):
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"""Return the texts of listed versions as a list of strings.
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Raises RevisionNotPresent if version is not present in
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return [''.join(self.get_lines(v)) for v in version_ids]
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def get_lines(self, version_id):
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"""Return version contents as a sequence of lines.
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Raises RevisionNotPresent if version is not present in
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raise NotImplementedError(self.get_lines)
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def _get_lf_split_line_list(self, version_ids):
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return [StringIO(t).readlines() for t in self.get_texts(version_ids)]
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def get_ancestry(self, version_ids, topo_sorted=True):
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"""Return a list of all ancestors of given version(s). This
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will not include the null revision.
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This list will not be topologically sorted if topo_sorted=False is
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Must raise RevisionNotPresent if any of the given versions are
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not present in file history."""
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if isinstance(version_ids, basestring):
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version_ids = [version_ids]
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raise NotImplementedError(self.get_ancestry)
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def get_ancestry_with_ghosts(self, version_ids):
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"""Return a list of all ancestors of given version(s). This
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will not include the null revision.
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Must raise RevisionNotPresent if any of the given versions are
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not present in file history.
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Ghosts that are known about will be included in ancestry list,
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but are not explicitly marked.
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raise NotImplementedError(self.get_ancestry_with_ghosts)
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@deprecated_method(one_four)
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def get_graph(self, version_ids=None):
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"""Return a graph from the versioned file.
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Ghosts are not listed or referenced in the graph.
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:param version_ids: Versions to select.
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None means retrieve all versions.
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if version_ids is None:
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result = self.get_parent_map(self.versions())
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pending = set(version_ids)
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this_iteration = pending
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parents = self.get_parent_map(this_iteration)
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for version, parents in parents.iteritems():
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result[version] = parents
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for parent in parents:
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for parents in result.itervalues():
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references.update(parents)
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existing_parents = self.get_parent_map(references)
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for key, parents in result.iteritems():
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present_parents = [parent for parent in parents if parent in
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result[key] = tuple(present_parents)
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@deprecated_method(one_four)
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def get_graph_with_ghosts(self):
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"""Return a graph for the entire versioned file.
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Ghosts are referenced in parents list but are not
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raise NotImplementedError(self.get_graph_with_ghosts)
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def get_parent_map(self, version_ids):
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"""Get a map of the parents of version_ids.
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:param version_ids: The version ids to look up parents for.
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:return: A mapping from version id to parents.
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raise NotImplementedError(self.get_parent_map)
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@deprecated_method(one_four)
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def get_parents(self, version_id):
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"""Return version names for parents of a version.
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Must raise RevisionNotPresent if version is not present in
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all = self.get_parent_map([version_id])[version_id]
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raise errors.RevisionNotPresent(version_id, self)
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parent_parents = self.get_parent_map(all)
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for version_id in all:
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if version_id in parent_parents:
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result.append(version_id)
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def get_parents_with_ghosts(self, version_id):
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"""Return version names for parents of version_id.
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Will raise RevisionNotPresent if version_id is not present
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Ghosts that are known about will be included in the parent list,
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but are not explicitly marked.
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return list(self.get_parent_map([version_id])[version_id])
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raise errors.RevisionNotPresent(version_id, self)
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@deprecated_method(one_four)
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def annotate_iter(self, version_id):
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"""Yield list of (version-id, line) pairs for the specified
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Must raise RevisionNotPresent if the given version is
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not present in file history.
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return iter(self.annotate(version_id))
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def annotate(self, version_id):
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"""Return a list of (version-id, line) tuples for version_id.
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:raise RevisionNotPresent: If the given version is
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not present in file history.
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raise NotImplementedError(self.annotate)
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def join(self, other, pb=None, msg=None, version_ids=None,
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ignore_missing=False):
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"""Integrate versions from other into this versioned file.
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If version_ids is None all versions from other should be
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incorporated into this versioned file.
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Must raise RevisionNotPresent if any of the specified versions
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are not present in the other file's history unless ignore_missing
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is supplied in which case they are silently skipped.
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self._check_write_ok()
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return InterVersionedFile.get(other, self).join(
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def iter_lines_added_or_present_in_versions(self, version_ids=None,
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"""Iterate over the lines in the versioned file from version_ids.
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This may return lines from other versions. Each item the returned
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iterator yields is a tuple of a line and a text version that that line
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is present in (not introduced in).
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Ordering of results is in whatever order is most suitable for the
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underlying storage format.
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If a progress bar is supplied, it may be used to indicate progress.
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The caller is responsible for cleaning up progress bars (because this
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NOTES: Lines are normalised: they will all have \n terminators.
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Lines are returned in arbitrary order.
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:return: An iterator over (line, version_id).
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raise NotImplementedError(self.iter_lines_added_or_present_in_versions)
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@deprecated_method(one_four)
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def iter_parents(self, version_ids):
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"""Iterate through the parents for many version ids.
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:param version_ids: An iterable yielding version_ids.
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:return: An iterator that yields (version_id, parents). Requested
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version_ids not present in the versioned file are simply skipped.
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The order is undefined, allowing for different optimisations in
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the underlying implementation.
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return self.get_parent_map(version_ids).iteritems()
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def plan_merge(self, ver_a, ver_b):
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"""Return pseudo-annotation indicating how the two versions merge.
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This is computed between versions a and b and their common
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Weave lines present in none of them are skipped entirely.
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killed-base Dead in base revision
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killed-both Killed in each revision
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unchanged Alive in both a and b (possibly created in both)
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ghost-a Killed in a, unborn in b
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ghost-b Killed in b, unborn in a
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irrelevant Not in either revision
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raise NotImplementedError(VersionedFile.plan_merge)
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def weave_merge(self, plan, a_marker=TextMerge.A_MARKER,
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b_marker=TextMerge.B_MARKER):
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return PlanWeaveMerge(plan, a_marker, b_marker).merge_lines()[0]
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class _PlanMergeVersionedFile(object):
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"""A VersionedFile for uncommitted and committed texts.
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It is intended to allow merges to be planned with working tree texts.
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It implements only the small part of the VersionedFile interface used by
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PlanMerge. It falls back to multiple versionedfiles for data not stored in
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_PlanMergeVersionedFile itself.
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def __init__(self, file_id, fallback_versionedfiles=None):
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:param file_id: Used when raising exceptions.
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:param fallback_versionedfiles: If supplied, the set of fallbacks to
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use. Otherwise, _PlanMergeVersionedFile.fallback_versionedfiles
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can be appended to later.
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self._file_id = file_id
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if fallback_versionedfiles is None:
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self.fallback_versionedfiles = []
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self.fallback_versionedfiles = fallback_versionedfiles
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def plan_merge(self, ver_a, ver_b, base=None):
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"""See VersionedFile.plan_merge"""
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from bzrlib.merge import _PlanMerge
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return _PlanMerge(ver_a, ver_b, self).plan_merge()
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old_plan = list(_PlanMerge(ver_a, base, self).plan_merge())
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new_plan = list(_PlanMerge(ver_a, ver_b, self).plan_merge())
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return _PlanMerge._subtract_plans(old_plan, new_plan)
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def plan_lca_merge(self, ver_a, ver_b, base=None):
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from bzrlib.merge import _PlanLCAMerge
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graph = self._get_graph()
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new_plan = _PlanLCAMerge(ver_a, ver_b, self, graph).plan_merge()
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old_plan = _PlanLCAMerge(ver_a, base, self, graph).plan_merge()
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return _PlanLCAMerge._subtract_plans(list(old_plan), list(new_plan))
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def add_lines(self, version_id, parents, lines):
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"""See VersionedFile.add_lines
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Lines are added locally, not fallback versionedfiles. Also, ghosts are
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permitted. Only reserved ids are permitted.
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if not revision.is_reserved_id(version_id):
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raise ValueError('Only reserved ids may be used')
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raise ValueError('Parents may not be None')
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raise ValueError('Lines may not be None')
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self._parents[version_id] = tuple(parents)
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self._lines[version_id] = lines
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def get_lines(self, version_id):
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"""See VersionedFile.get_ancestry"""
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lines = self._lines.get(version_id)
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if lines is not None:
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for versionedfile in self.fallback_versionedfiles:
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return versionedfile.get_lines(version_id)
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except errors.RevisionNotPresent:
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raise errors.RevisionNotPresent(version_id, self._file_id)
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def get_ancestry(self, version_id, topo_sorted=False):
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"""See VersionedFile.get_ancestry.
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Note that this implementation assumes that if a VersionedFile can
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answer get_ancestry at all, it can give an authoritative answer. In
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fact, ghosts can invalidate this assumption. But it's good enough
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99% of the time, and far cheaper/simpler.
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Also note that the results of this version are never topologically
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sorted, and are a set.
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raise ValueError('This implementation does not provide sorting')
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parents = self._parents.get(version_id)
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for vf in self.fallback_versionedfiles:
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return vf.get_ancestry(version_id, topo_sorted=False)
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except errors.RevisionNotPresent:
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raise errors.RevisionNotPresent(version_id, self._file_id)
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ancestry = set([version_id])
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for parent in parents:
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ancestry.update(self.get_ancestry(parent, topo_sorted=False))
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def get_parent_map(self, version_ids):
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"""See VersionedFile.get_parent_map"""
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pending = set(version_ids)
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for key in version_ids:
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result[key] = self._parents[key]
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pending = pending - set(result.keys())
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for versionedfile in self.fallback_versionedfiles:
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parents = versionedfile.get_parent_map(pending)
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result.update(parents)
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pending = pending - set(parents.keys())
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def _get_graph(self):
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from bzrlib.graph import (
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_StackedParentsProvider,
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from bzrlib.repofmt.knitrepo import _KnitParentsProvider
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parent_providers = [DictParentsProvider(self._parents)]
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for vf in self.fallback_versionedfiles:
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parent_providers.append(_KnitParentsProvider(vf))
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return Graph(_StackedParentsProvider(parent_providers))
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class PlanWeaveMerge(TextMerge):
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"""Weave merge that takes a plan as its input.
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This exists so that VersionedFile.plan_merge is implementable.
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Most callers will want to use WeaveMerge instead.
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def __init__(self, plan, a_marker=TextMerge.A_MARKER,
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b_marker=TextMerge.B_MARKER):
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TextMerge.__init__(self, a_marker, b_marker)
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def _merge_struct(self):
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def outstanding_struct():
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if not lines_a and not lines_b:
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elif ch_a and not ch_b:
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elif ch_b and not ch_a:
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elif lines_a == lines_b:
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yield (lines_a, lines_b)
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# We previously considered either 'unchanged' or 'killed-both' lines
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# to be possible places to resynchronize. However, assuming agreement
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# on killed-both lines may be too aggressive. -- mbp 20060324
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for state, line in self.plan:
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if state == 'unchanged':
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# resync and flush queued conflicts changes if any
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for struct in outstanding_struct():
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if state == 'unchanged':
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elif state == 'killed-a':
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elif state == 'killed-b':
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elif state == 'new-a':
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elif state == 'new-b':
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elif state == 'conflicted-a':
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elif state == 'conflicted-b':
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assert state in ('irrelevant', 'ghost-a', 'ghost-b',
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'killed-base', 'killed-both'), state
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for struct in outstanding_struct():
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class WeaveMerge(PlanWeaveMerge):
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"""Weave merge that takes a VersionedFile and two versions as its input."""
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def __init__(self, versionedfile, ver_a, ver_b,
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a_marker=PlanWeaveMerge.A_MARKER, b_marker=PlanWeaveMerge.B_MARKER):
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plan = versionedfile.plan_merge(ver_a, ver_b)
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PlanWeaveMerge.__init__(self, plan, a_marker, b_marker)
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class InterVersionedFile(InterObject):
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"""This class represents operations taking place between two VersionedFiles.
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Its instances have methods like join, and contain
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references to the source and target versionedfiles these operations can be
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Often we will provide convenience methods on 'versionedfile' which carry out
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operations with another versionedfile - they will always forward to
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InterVersionedFile.get(other).method_name(parameters).
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"""The available optimised InterVersionedFile types."""
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def join(self, pb=None, msg=None, version_ids=None, ignore_missing=False):
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"""Integrate versions from self.source into self.target.
748
If version_ids is None all versions from source should be
749
incorporated into this versioned file.
751
Must raise RevisionNotPresent if any of the specified versions
752
are not present in the other file's history unless ignore_missing is
753
supplied in which case they are silently skipped.
756
version_ids = self._get_source_version_ids(version_ids, ignore_missing)
757
graph = Graph(self.source)
758
search = graph._make_breadth_first_searcher(version_ids)
759
transitive_ids = set()
760
map(transitive_ids.update, list(search))
761
parent_map = self.source.get_parent_map(transitive_ids)
762
order = tsort.topo_sort(parent_map.items())
763
pb = ui.ui_factory.nested_progress_bar()
766
# TODO for incremental cross-format work:
767
# make a versioned file with the following content:
768
# all revisions we have been asked to join
769
# all their ancestors that are *not* in target already.
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# the immediate parents of the above two sets, with
771
# empty parent lists - these versions are in target already
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# and the incorrect version data will be ignored.
773
# TODO: for all ancestors that are present in target already,
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# check them for consistent data, this requires moving sha1 from
776
# TODO: remove parent texts when they are not relevant any more for
777
# memory pressure reduction. RBC 20060313
778
# pb.update('Converting versioned data', 0, len(order))
780
for index, version in enumerate(order):
781
pb.update('Converting versioned data', index, total)
782
if version in target:
784
_, _, parent_text = target.add_lines(version,
786
self.source.get_lines(version),
787
parent_texts=parent_texts)
788
parent_texts[version] = parent_text
793
def _get_source_version_ids(self, version_ids, ignore_missing):
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"""Determine the version ids to be used from self.source.
796
:param version_ids: The caller-supplied version ids to check. (None
797
for all). If None is in version_ids, it is stripped.
798
:param ignore_missing: if True, remove missing ids from the version
799
list. If False, raise RevisionNotPresent on
800
a missing version id.
801
:return: A set of version ids.
803
if version_ids is None:
804
# None cannot be in source.versions
805
return set(self.source.versions())
808
return set(self.source.versions()).intersection(set(version_ids))
810
new_version_ids = set()
811
for version in version_ids:
814
if not self.source.has_version(version):
815
raise errors.RevisionNotPresent(version, str(self.source))
817
new_version_ids.add(version)
818
return new_version_ids